Description

Dark energy, what exactly does it do? Find out in this episode of Space Time! Part 3 in our Dark Energy series. Part 1: https://www.youtube.com/watch?v=xZTb6sfHEX8Part 2: https://www.youtube.com/watch?v=-4PayaEgEZc____________________________________________________________

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How does dark energy affect the universe's expansion? Measuring past expansion history should tell us the future expansion without ever having to count any galaxies. To measure this we need to measure the redshift-distance relationship, which we will talk about in detail in this episode.